Guyed tower for microwave horns



Dec. 22, 1970 R. J. EBERLE 3,550,146 GUYED TOWER FOR MICROWAVE HORNS IFiled March 1. 1967 6 Sheets-Sheet 1 l-libillll 3 usan-1 294 INVENTOR.RICHARD J [BE/7L5 A TTORNEYS Dec. 22, 1970 J. EBERLE 7 3,550,145

GUYED TOWER FOR MICROWAVE HORNS Filed March 1., 1967 1 6 Sheets-Sheet i.

INVENTOR. RICHARD J. EBERLE Lam a a ATTORNEYS Dec. 22, 197-0 R. J.EBERLE 3,550,146

GUYED TOWER FOR MICROWAVE HORNS Filed March 1, 1967 6 Sheets-SheetsINYENTOR. mew/1R0 J. 5195/21.!

ATTORNEYS Dec. 22, 1970 R. J. E BERLE GUYED TOWER FOR MICROWAVE HORNS 6Sheets-Sheet 4 Filed March v1, 1967 INVENTOR. RICHARD J. EEERLE BY f 4 IATTORNEYS 1970 R. J. EBERLE 3,550,146

GUYED TOWER FOR MICROWAVE HORNS Filed March 1, 1967 6 Sheets-Sheet 5 vhas I M544 INVENTOR.

RICHARD J. EBERLL' Q BY ATTORNEYS Dec. 22, 1970 R4, EB'ERLE 3,550,146

GUYED TOWER FOR MICROWAVE HORNS Filed March 1. 1967 6 She etS-Sheet a AII L am F/ /0 INVENTOR. RICHARD J. EBERLE ATTORNEYS United States PatentUS. Cl. 343-879 7 Claims ABSTRACT OF THE DISCLOSURE A guyed tower forsupporting microwave horns having three platforms. The upper twoplatforms accept three horns each at 120 spacing over full 360. A thirdplatform is provided for passive devices. Tower includes adjustable waveguide supports and wave guide bridge.

Guyed and self-supporting antenna towers have heretofore beenconstructed and used. Such towers are normally designed and built for aspecific use with little or no thought being given to the provision of atower with sufficient flexibility that it can be modified to take onadditional electronic handling characteristics once it is completed. Thepresent invention relates to a guyed microwave tower which is designedto support between 1 and 6 microwave horns. The number of horns can bechanged at any time after the tower has been completed. Thus, thepresent invention provides a tower which permits expansion of facilitiesin the future with only moderate additional costs as compared to thecost of completely redesigning and erecting a new tower.

The present invention relates to a guyed microwave tower in the rangefrom 100 to 400 feet which is capable of meeting the high specificationand standards set forth by the telephone companies. The tower includesan upper and lower platform for mounting three horn reflector antennaseach. The reflectors are mounted at angles of 120 on their respectiveplatforms, and the upper and lower platforms are displaced 60 withrespect to each other. Thus, when a tower carries a full complement ofsix horn reflectors, they cover a full 360 at spaced angles of 60. Athird platform is provided for supporting passive reflectors if desired.The tower is so designed so that it can be initially constructed withone platform with provision for adding the second platform at a latertime.

Adjustable wave guide supports are provided and a novel bridge structureadjacent the transmitter building is provided for supporting andprotecting the wave guides.

For the purpose of illustrating the invention, there is shown in thedrawings a form which is presently preferred; it being understood,however, that this invention is not limited to the precise arrangementsand instrumentalities shown.

FIG. 1 is an elevational view of a guyed tower constructed in accordancewith the present invention and including a wave guide bridge structurefor supporting the wave guides into a transmitter building.

FIG. 2 is a top plan view of the upper platform illustrated in FIG. 1taken along the line 2-2.

FIG. 3 is a partial sectional view of the platform illustrated in FIG. 2taken along the line -3--3.

FIG. 4 is a top plan view of the lower platform il lustrated in FIG. 1taken along the line 4 -4.

FIG. 5 is a partial perspective view of the tower structure.

FIG. 6 is a plan view of the tower structure illustrated in FIG. 5 takenalong the line 66.

FIG. 7 is a partial sectional view of the flange connection for thevertical supporting member illustrated in FIG. 1 taken along the line7-7.

FIG. 8 is a partial sectional view illustrating the adustable wave guidesupport of FIG. 5 taken along the line 88.

FIG. 9 is a plan view of the wave guide supporting bridge.

FIG. 10 is a sectional view of the wave guide supporting bridgeillustrated in FIG. 9 and taken along the line 10-10.

Referring now to the drawings in detail, wherein like numerals indicatelike elements, there is shown in FIG. 1 a guyed microwave horn reflectortower designated generally as 10.

As shown, the tower 10 is vertically supported on a base 12 andlaterally supported by one or more levels of guy wires. By way ofexample, three levels 14, 16 and 18 are shown. The guy wires 14, 16 and18 extend from the vertical tower members to be described below and areanchored as at 20. The base 12 and anchors 20 are conventional.Accordingly, they will not be described in detail. The special saddleconnection between the guy wires and the tower is described below.

The tower 10 is constructed to support six microwave horn reflectorssuch as the reflectors 22, 24 and 26. The reflectors 22, 24 and 26 formno part of this invention and will not be described in detail except toindicate that their function is to reflect and transmit microwaves. Eachof the reflectors is connected to a wave guide, such as wave guides 28and 30, which pass through wave guide restrainers supported on the tower10 aggl a 'wave guide bridge 34 into the transmitter building Referringnow to the remaining figures of the drawing, the tower 10 will bedescribed in detail.

FIGS. 2 and 3 illustrate the uppermost platform 38 and the supportingstructure therefor, as well as a detailed view of the support for hornreflector 24. The platform illustrated in FIG. 2 is shown with thegrating in position except on one of the legs wherein it has beenremoved to show the detail of the structural elements.

As shown, the upper platform 38 is constructed to define three legs 40,42 and 44 extending from the central tower 10 at angles of 120 withrespect to each other. Each leg is constructed by fixing a plate, suchas gussets 46, 48 and 50 to one of the vertical support members 52, 54and 56. The main frame is defined by channel members 58, 60 and 62 whichare bolted or otherwise fixed to the gussets 46, 48 and 50 to define atriangle rotated 60 from the triangle defined by the vertical supportmembers. Extending outwardly from the channel member 58 are a pair ofparallel channel members 64 and 66 which are joined to the gussets 68and 70. A channel member 72 extends across the channel members 64 and 66and is also joined to the gussets 68 and 70. Outer angle members 74, 76,78, and 82 are joined endwise and to the channel members 58, 64, 66, and72 to define the outer perimeter of the platform leg 42. Angle members84 and 86 extend at an angle from gussets 68 and 70 to gussets 88 and90. Similar angle members such as 92 and 94 are provided for each of theplatform legs so that when completely assembled, they define a trianglesupport with sides generally parallel to the side 10. This lattertriangle is not a true triangle in the sense that the angle membersdefining its sides do not join each other to form the triangle apices.

The leg 42 described above is constructed to support a horn reflectorwithin the opening defined by the angle members 64, 66, 72 and 96. Theparallel angle members such as 6474; 72-78; and 66-82 are adapted toreceive removable gratings illustrated schematically as 98 on Which aworkman can move about the horn microwave reflector.

Referring now to FIG. 3, a sectional view of the platform legillustrates the manner in which the horn reflector is supported. Leg 40is identical with previously described leg 42. Accordingly, likeelements have been designated with like numerals except a prime has beenadded. In addition, FIG. 3 illustrates how the safety railing 100 issupported over the perimeter of the platform 38 by posts 102 which areconnected to the outer angle members,

The platform leg 40 receives additional support by means of the anglemember 104 which extends outwardly from a gusset 106 that is fixed tothe vertical support member 56. At its opposite end it is fixed to agusset 108 depending from the angle member 66. As shown in FIG. 2, asimilar angle member 110 extends from the post 52 to the angle member64.

The horn reflector 24 extends through the opening in the platform leg 40and is supported therein by conventional means which are not shown.

The entire platform 38 is constructed so that it can be partly or whollyassembled at ground level and then hauled to the top of the tower forinstallation. If the tower is originally intended for use for three orless horn reflectors, then the upper platform is not installed. However,if additional facilities are needed, then the platform can be assembledand mounted at the top of the tower to provide support for threeadditional horn reflectors. It should be noted that the longitudinalaxis of each leg 40, 42 and 44 of the platform 38 extends outwardly fromthe vertical supporting members 52, 54 and 56. As will be explainedbelow, central longitudinal axes of the legs of the lower platformextend outwardly from the center of the sides defined by the towerstructure. Thus, the legs of the lower platform are displaced 60 fromthe legs of the upper platform.

The structure of lower platform 114 is generally similar to that ofupper platform 38. Thus, it is constructed to define three platform legs116, 118 and 120 at angles of 120 with respect to each other. Since allthree legs are similarly constructed, only leg 120 will be described indetail.

As shown, channel members 122 and 124 extend outwardly from gussets 126and 128 fixed to the vertical support members 48 and 56. A channelmember 130 extends between channel members 122 and 124 and is fixed incommon with them to the gussets 132 and 134. A similar channel member136 extends between and is fixed to channel members 122 and 124 as wellas to gusset 138. Channel members 122, 124, 130 and 136 define anopening in which a horn reflector can be supported. Reinforcing anglemembers 140 and 142 extend from gussets 126 and 128 to gusset 138.Channel members 144 and 146 extend from channel members 122 and 124 togussets 148 and 150 and angle members 152 and 154 extend from gussets148 and 150' to gussets 126 and 128.

Gussets 148 and 150 are fixed to channel members 156 and 158 which arecommon to leg 120 as well as legs 116 and 118. Angle members 160 and 162extend from channel members 156 and 158 and are joined by angle member164. Angle member 164 is in turn fixed to angle members 168 and 170 andto channel members 166 and 172 which extend between it and gussets 132and 134. Parallel members 122-162; 130-164; and 124160 are fitted withremovable grating plates 174 which provide a walking surface on theplatform for workmen.

Each leg of the platform 114 receives vertical support by parallel anglemembers 176 and 178 which extend upwardly and outwardly from thevertical support members 52 and 56 to the gussets 132 and 134.

The perimeter of platform 114 is bounded by a safety railing 180 whichis supported by posts extending upwardly from the outermost anglemembers.

A horn reflector 182 is shown mounted in the opening in leg 116. Noreflector is mounted in leg 118. Accordingly, the opening is showncovered by removable gratings 184 and 186.

Lower platform 114 is permanently fixed to the tower 10 and would beconstructed with such a tower regardless of the number of reflectors tobe supported by it.

Referring now to FIGS. 5 and 6, there is shown a detailed view of thetower structure. The primary tower support is provided by verticalsupport members 52, 54 and 56 which are preferably 3% inch diametersolid steel rods bolted together in .25 foot lengths as shown in FIG. 7.A flange 188 is welded to the lower vertical member 54a and a flange 190is welded to the upper vertical member 54b. The flanges 188 and 190 arespaced approximately A; of an inch away from the end surface of thevertical members 54a and 54b. Thus, a gap 192 of approximately fii of aninch appears between the flanges 188 and 190 when the vertical members54a and 54b are brought into abutment. Four bolts 194 hold the flanges188 and 190 together. The advantage of providing a gap between theflanges is so that the vertical members 54a and 54b can be held tightlytogether when the bolts 194 are drawn up.

Gusset plates are welded at regular intervals along the length of thevertical members 52, 54 and 56. In the preferred embodiment, the 25-footvertical sections have sets of gusset plates mounted at each end and atintervals of six feet three inches. Typical sets of gussets areillustrated in FIGS. 5 and 6. Each set of gussets includes two plates196 and 198 welded to the vertical members so as to define an angle of60 betwen their planar surfaces. Typical sets of gussets includinggusset plates 196, 198, 200, 202, 204, 206, 208, 2.10, and 212, 218 areillustrated in FIGS. 5 and 6.

Cross members are provided at each level defined by the three sets ofgussets. As shown in FIGS, 5 and 6, the cross members are designated bythe numerals 216, 218 and 220 at one level and by the numerals 222, 224and 226 at the next higher level.

Each cross member consists of a pair of angle pieces 228 and 230 boltedback-to-back on either side of a gusset plate. Thus, the angle pieces228 and 230 shown in FIG. 6 are bolted at their ends to the gussetplates 1% and 200 and with their dependent angle plates at the top andextending laterally outward. The cross members are thus assembled toprovide lateral internal support for the vertical members 52, 54 and 56.

Extending diagonally between each two sets of gussets are crossedtension rods to truss the tower and provide the necessary rigidity. FIG.5 illustrates the manner in which the tension rods are positioned. Thus,tension rod 232 is bolted to gusset 196 and extends diagonally to gussetplate 208. Similarly, tension rod 234 is bolted to gusset plates 200 and204. In a similar manner, identical tension rods extend between gussetplates on each side of the tower as defined by the vertical members 52,54 and 56. Each tension rod is locked to its mate by a locking device238. Such locking devices are conventional. One such device is readilyobtained in a market under the name Wrap Lock.

As shown in FIG. 1, the wave guides 28 and 30 depend downwardly from themicrowave horns 24 and 22. In accordance with the principles describedherein, the wave guides for each of the horns are unsupported except atthe horns and at the bridge 34. Intermediate of these support points,the wave guides are merely restrained by the wave guide restrainers 32.One such wave guide restrainer 32 is illustrated in FIG. 8. As shown,the restrainer 32 includes a collar 240 which is clamped to the verticalsupport member 54 by bolts (not shown). An arm 242 is Welded to thecollar 240 and extends laterally therefrom. An extension arm 246 isbolted to arm 242 by bolts 248 which extend through slotted holes so asto provide adjustment for the overall combined extension of arms 242 and246.

A cylinder 250 is fixed to the distal end of arm 256 by means of areleasable wire clamp 252. Cylinder 250 is flared at its end as shown.

The wave guide 30, whose outer diameter is substantially smaller thanthe inner diameter of cylinder 250 passes through it and is looselyrestrained thereby.

As shown in FIG. 1, the wave guide restrainers attached to the verticalsupport members 52, 54 and 56 are positioned at every other level ofcross arms. The amount of the lateral extension for the wave guiderestrainers 32 is dictated by conventional electronic principles forwave guides. The principles for correctly arranging the curvature of thewave guide are well known and therefore need not be discussed in detail.However, the use of adjustable wave guide restrainers permits thecurvature to be precisely adjusted so as to obtain maximum transmissionefficiency.

As illustrated in FIG. 1, and also in FIG. 5, the guy wires are boltedto gussets 254 which are welded to the vertical support members 52, 54and 56. Intermediate the terminal socket 258 on each guy wire and thegusset 254 is a saddle member 256. Saddle member 256 comprises a pair ofspaced apart side pieces 258 and 260 which are fixed in position by topand bottom plates 264 and 266 that are welded thereto. The spacingbetween side pieces 258 and 260 is substantially wider than the width ofone of the wave guides such as wave guide 28. Thus, the wave guides canextend freely along the length of the tower defined by the verticalsupport members without interference with the guy wires.

Saddle member 256 is connected to the terminal socket 258 and gusset 254by pins 270 and 268 which extend therethrough and are held in positionby cotter pins or the like.

The foregoing describes the means for supporting and restraining thewave guides which depend from microwave horns mounted on the uppermostplatform. As explained above, the uppermost platform legs 40, 42 and 44extend outwardly from the apices of the triangle defined by the verticalsupport members 50, 52 and 56. On the other hand, the legs for the lowerplatform 114 extend outwardly from a point intermediate the sides of thetriangle defined by the vertical support members 52, 54 and 56.

To guide and restrain the wave guides which depend from the hornsmounted on the lower platform 114, a support has been provided at everyother level of cross members.

One such support is illustrated in FIG. wherein three angle members 272,274 and 276 are shown mounted on the cross members 216, 218 and 220. Theangle members 272, 274 and 276 are mounted so as to define a trianglewith its apices extending from and disposed intermediate the sides ofthe triangle defined by the cross members 216, 218 and 220. Statedotherwise, the apices of the triangle defined by the angle members 272,274 and 276 define an included angle of 60 with the apices defined bythe cross members 216, 218 and 220.

As best shown in FIG. 6, angle members 272, 274 and 276 are joined attheir apices by braces 278 and 280. The braces extend between adjacentangle members and also serve to support the inner arm 242 for a waveguide restrainer 32. Only the arms 242 are shown inasmuch as theremainder of the wave guide restrainers 32 which are attached to theangle members are identical with those shown in FIG. 8.

The angle members 272, 274 and 276 also serve another function. A ladder282 is fixed to them and thereby supported within the tower structure.If desired, gratings 284 can be mounted at the various levels forproviding a space upon which a workman can stand to adjust the waveguide restrainers.

In the preferred embodiment, the tower is provided with a third platform290 for supporting additional electronic reflectors if desired. In thepreferred embodiment,

the platform 290 is in reality three levels 292, 294 and 296 which areidentical in structure and spaced approximately six feet above eachother. The levels are constructed by providing a triangular shapedmember attached to the vertical support members 52, 54 and 56 and thenadditional brace members are attached to the triangular member. Theadditional members define the perimeter of each platform level in theshape of a hexagon.

An additional feature of the present invention, a truss bridge structureis provided for supporting the wave guides from the tower 10 into thetransmitter building 36.

As shown in FIGS. 9 and 10, the wave guide bridge 34 surrounds the tower10 at its base 12. The bridge structure 34 is spaced from the tower 10by a distance equal to the distance of the wave guides 300 from thetower. By way of example, six wave guides 300 have been illustrated asif the tower 10 were supporting six microwave horns.

The bridge 34 is supported on four braced legs 302, 304, 306 and 308which are fixed to reinforce concrete footings 310, 312, 314 and 316.The legs 302-308 are in the nature of truncated A frames which supportthe bridge trusses 318, 320 and 322 as well as the cross trussses 324.326 and 328.

All of the trusses are constructed of angle pieces assembled to definerectangular tunnels such as tunnels 330 and 332 in trusses 318 and 320.As shown in FIG. 1, appropriate cross bracing is provided formaintaining rigidity in the bridge trusses. The top of each bridge trussis fitted with cover plates 334.

Appropriate clamps for the wave guides 300 are provided to support waveguides as they extend into the opening 336 in the transmitter building36.

The bridge 34 provides functional rigidity for supporting the waveguides at the ground level. Although the bridge is shown as supportingonly six wave guides, it is designed to support as many as twenty-fourwave guides when necessary.

The foregoing description of the structural details should make theadvantages of the tower 10 readily apparent. Among the advantages arethe fact that the tower can be assembled in twenty-five foot sections atground level. Thereafter, the sections can be raised and bolted intoposition. All elements in the tower are bolted together to furthersimplify the assembly and erection. Another advantage as explainedbefore, is the modular construction that allows for the installation ofa first platform for supporting three microwave horns and then a secondplatform for supporting an additional three microwave horns when addedfacilities are required.

The use of a guyed tower in communications is an additional advantagebecause of its economy. Moreover, the guyed tower of the presentinvention more than meets the necessary rigidity required in telephonecommunication. The structure of the present invention is capable ofwithstanding wind velocities of over 112 miles per hour; or statedotherwise, 50 pounds per square foot wind load. The rigidity of thetower at 20 pounds per square foot (70 mph.) is as follows.

Deflection plus or minus 0.25 Twist plus or minus 0.50

To obtain the design specifications, the vertical support members are 3%inch diameter solid steel. The cross members are 2 x 2% x angle steeland the tension rods are of an inch in diameter. All gusset plates forsupporting the cross members and tension rods are /2 inch steel. Theupper guy wires attached to the bottom of the lower platform have a teststrength of 150,000 pounds and the lower guy wires have test strengthsof approximately 80,000 pounds.

The tower is relatively light in relation to its load capacity whichincludes three microwave horn reflectors on the top platform and threemicrowave horn reflectors.

on the lower platform as well as a capacity for two 8 x 12 passivereflectors on the platform 290. Each set of three horn reflectors coversa full 360.

The present tower is designed to provide top platform heights rangingfrom 100 to 400 feet in multiples of 12 feet 6 inches.

The present invention may be embodied in other specific forms withoutdeparting from the spirit or essential attributes thereof and,accordingly, reference should be made to the appended claims, ratherthan to the foregoing specification as indicating the scope of theinvention.

I claim:

1. A guyed tower comprising a base, upright vertical support members,horizontal cross members joining said vertical support members, tensionrods extending diagonally between said cross members for reinforcingsaid tower, a first microwave horn supporting platform mounted adjacentthe top of said tower, said first platform including at least twoequiangularly spaced legs extending laterally from said tower, each ofsaid legs including means for supporting a microwave horn, a removablesecond platform mounted above said first platform, said second platformhaving at least two equiangularly spaced legs extending laterally fromsaid tower, each of said second platform legs including means forsupporting a microwave horn, said second platform legs being spacedangularly intermediate said first platform legs.

2. A tower in accordance with claim 1 wherein the tower structurecomprises a plurality of assembled tower sections, each section beingconnected by joining the vertical support members in abutting relation.

.3. A tower in accordance with claim 2 wherein said individual sectionscomprise three vertical support members, spaced cross members extendingbetween said support members and connected thereto, each of said crossmembers including a pair of angle members bolted to a gusset on saidvertical members, said tension rods extending diagonally between saidcross members and being bolted to said gusset on each side of said towerdefined by the three vertical support members, a flange adjacent eachend of each vertical support member, each said flange being spaced awayfrom the end of said vertical support members, said vertical supportmembers of one section being aligned in abutting relation with thevertical support members of another section, and bolts extending betweenadjacent flanges of adjacent sections to retain such sections.

4. A tower in accordance with claim 1 including a wave guide supportbridge between said tower base and a transmitter building, said bridgeincluding at least three longitudinal wave guide channels, and waveguide retaining means mounted within said channels.

5. A tower in accordance with claim 1 wherein said tower has three sidesdefined by the spaces between three vertical support members, one ofsaid platforms being disposed with the longitudinal axis of threeplatform legs extending each from a vertical support member, the otherof said platforms being disposed with the longitudinal axis of threeplatform legs extending each from the side of said tower, and aplurality of wave guide restrainers extending from the tower below eachof the legs, said wave guide restrainers below said platform legsextending from said vertical support members being fixed to saidvertical support members, and the wave guide restrainers below saidplatform legs extending from the tower sides being supported by supportmeans extending from said cross members.

6. A tower in accordance with claim 1 including guy wires extending fromsaid vertical support members, said guy wires being connected to saidvertical support members by a saddle, said saddle including guy wire andtower connecting means disposed at opposite ends, and spaced apart sidepieces connecting said guy wire and tower connecting means, said sidepieces and said guy wire and vertical support connecting means definingan opening in said saddle for receiving a wave guide therethrough.

7. A tower in accrdance with claim 1 including a wave guide supportbridge extending between said tower base and a transmitter building,said bridge including longitudinal wave guide channels disposedcompletely around said tower, and wave guide channels extending fromsaid first mentioned channels to an opening in said transmitterbuilding, each said channel including wave guide restraining means forretaining wave guides in said channels.

References Cited UNITED STATES PATENTS OTHER REFERENCES Broadcast News,vol. 59, November 1950, 'Reprint 3 sheets, copy 343-874.

Tower Construction Catalog, February 1959, cover page, p. 1 of MicrowaveReflectors, p. 3 of Microwave Tower; copy 343-700c.

ELI LIEBERMAN, Primary Examiner US. Cl. X.R. 343890

